Improvement in blackboard-rubbers



B L A C K B 0 A R D R U B B E R.

' Patented March 13 187 7.

CZEIARLES N. BACON, OF WINCHESTER, MASSACHUSETTS.

IMPROVEMENT IN BLACKBOARD-RUBBERS.

Specification forming part of Letters Patent No. 188,227, dated March13, 1877 application filed December 18, 1876.

To all whom it may concern Be it known that I, CHARLES N. BACON, ofWinchester, in the county of Middlesex and State of Massachusetts, haveinvented certain new and useful Improvements in Blackboard-Erasers; andI do hereby declare that the following isa folk-clear, and. exactdescription thereof, which will enable others skilled in the art towhich it appertains to make and use the same, reference being bad to theaccompanying drawings, and to the letters of reference marked thereon,which form a part of this specification.

My invention relates to improvements in blackboard-erasers; and consistsof a wedgeshaped piece offelt or suitable porous and textile or fibrousmaterial, to the base of which is secured a handle, by which the erasercan be held and operated.

This isa great improvement over the ordinary blaokboard-erasers,inasmuch as all the sides of my eraser can be used to great advantagefor erasing large surfaces, at the same time that I am enabled, by thepecu liarity of the wedge shape, to erase single lines on the blackboardwithout disturbing lines in close proximity to those that are to beerased. On this account my improved eraser is particularly adapted forart schools, geometrical or mechanical drawing schools, as

well as the lecture-room. It is, at the same time, a very convenient anddurable eraser for ordinary school purposes.

-On the accompanying drawing, Figure 1 represents a perspective view ofmy improved blackboard-eraser, and Fig. 2 represents a centrallongitudinal section of the same.

Similar letters refer to similar parts wherever they occur on thedifferent parts of r the drawing.

(it represents the Wedge-shaped piece of felt or suitable material,tapering from its 'base a to an edge, a", as shown. Only two' of thesides of the wedge are shown tapering in the drawing, the other twobeing shown parallel; but I may also make all sides tapering to an edgeor point when so desired. 11 represents the handle, extending in a linewith the wedge from its base, and is provided with a suitable shank orprojection, c, that is insertedinto the eraser a, and secured thereto bymeansjof glue, cement, or in any ordinary manner.

Any of the surfaces of the wedge 00 are to be used for erasing surfacesor lines on the blackboard, and the edge or point a isto be used for thepurpose of erasing single lines without disturbing other lines in closeproximity thereto.

Having thus fully described the nature, construction, and operation ofmy invention, I wish to secure by Letters Patent, and claim- Thehereindescribed improved blackboarderaser, consisting of thewedge-shaped piece of felt or its equivalent, a, in combination with thehandle b, substantially as and for the purpose set forth and described.

In testimonythat I claim the foregoing as my own invention I haveaflixed my signature in presence of two witnesses.

CHARLES N. BACON. Witnesses:

ALBAN ANDRE'N, HENRY CHADBOURN.

